hamilton



Jan. 24, 1956 F. HAMILTON CHAIR BASE 2 Sheets-Sheet 1 Filed May 12, 1953I N V EN TOR. 57/21 f'fl/m/z ra/v,

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Jan. 24, 1956 E. F. HAMILTON 2,732,157

CHAIR BASE Filed May 12, 1953 2 Sheets-Sheet 2 11111:; i "I" .anu'lllINVENTOR.

24 ITTaP/YFYS.

r 2,732,157 Patented Jan. 24, 1956 CHAIRBASE Earl F. Hamilton, Columbus,Ind. Application May 12, 1953, Serial No. 354,509

Claims. (Cl. 248-194) This invention relates to articles of furnitureand more particularly to legs for furniture and to means for holding acaster pin therein and for providing a resilient bumper face therefor.The invention is especially adapted for incorporation in a swivel-chairbase of common type having radiating legs formed of sheet-metal in aninverted U-shape cross-section.

It is an object of this invention to produce improved caster-holdingmeansespecially adapted for use in a chair leg of formed sheet-metal.Another object is to produce improved caster holding means of sturdyconstruction especially adapted for easy and economical assembly ontosuch a leg. A further object is to provide for such a leg a resilientbumper and cover face of economical construction and mode of attachment.

In carrying out my invention in a preferred embodiment, I form achair-base as a sheet-metal stamping having radiating legs of invertedU-shape in cross-section. At the outer end of each leg I provide acaster-socket in the form of two sheet-metal stampings having opposedfaces shaped to provide grooves which, when the two stampings aresecured together as by rivets, define a vertical passage for receiving acaster pin. One of such stampings has upper and lower tongues forconnection to the leg, the lower of such tongues being bent to providean upwardly open hook-portion adapted to embrace the lower edge of achair-leg wall, while the upper tongue extends along the inner face ofthe leg at the top thereof and is secured to the leg as by a rivet.Desirably, a trim-strip member covers and conceals the lower tongue atthe outer end of the leg and continues inwardly along the top of the legto conceal the lastmentioned rivet.

At the outer end of each leg, I provide a bumper of resilient rubber orlike material, such bumper comprising a web extending across the openbottom ofthe leg beneath the caster-socket and an upwardly extendingmarginal flange which embraces the lower edge of the leg across theouter'end thereof and fora distance inwardly along the sides ofthe leg.The web is provided with an opening for passage of the caster pin, andthe caster therefore holds the bumper in place.

Other objects and features of my invention will become apparent asthe'following description is understood, reference being had to thefollowing drawings, in which:

Fig. l is a side elevation of a chair embodying my invention; 7

Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1;

Fig. 3 is a fragmental radial section at a leg-end, taken on the line3-3 of Fig. 2;

Fig. 4 is an end elevation of a leg-end, with portions thereof brokenaway on the line 4-4 of Fig. 3;

Fig. 5 is a horizontal section taken on the line 5-5 of Fig. 3;

Fig. 6 is a bottom view of a leg-end; and

Fig. 7 is an isometric view of the bumper.

The chair shown in the drawings comprises a seat 10 supported by a rod14 extending from a base 18. Such a base comprises a series of radiatinglegs 20 all desirably formed as a single sheet-metal stamping, with eachleg of inverted U-shape in cross-section and having substantiallyvertical side walls 24 the lower edges of which are turned inwardly toprovide stiffening lips 26. The top wall 28 of each leg interconnectsthe side walls along their upper edges, such top wall 28 lying generallyhorizontally near the center of the base but curving gradually downwarduntil at the outer leg-end it is substantially vertical.

To provide a caster-socket adjacent each outer leg-end, I stamp fromheavy sheet-metal two pieces 30-32 formed to possess longitudinalgrooves to define, when the two pieces are held juxtaposed by rivets 34,a vertical passage or opening adapted to receive the pin 36 and thepincarried expandible retaining ring 38 of a caster 40.

The outer stamping 32 is provided at its lower end with a tongue 44which extends radially of the leg to end in an upwardly-open U-shapedhook portion 46 adapted to embrace the edge of the leg wall 28 at theend of the leg. Near the top of the caster-socket, one of the stamp ings30-32, shown here as stamping 32, is provided with an upper tongue 52,which tongue is bent to extend inwardly along and conform to the lowersurface of the leg-wall 28, to be secured thereto as by rivet 56. Thetransverse engagement of the tongue 52 and wall 28 in the region of therivet connection 56, as well as the transverse engagement of hook 46 oflower tongue 44 with the wall 28, prevent any, rotation of thecaster-holding assembly 30-32 about such connection 56; hence a singlepoint connection, such as the single rivet 56 shown, is sufficient bothto positively position vertically and hori zontally the upper end of thesocket 30-32 and to oppose downward movement of such socket duringcaster-withdrawal.

If both tongues 44 and 52 extend from the same stamping 32, as shown,the other stamping 30 need be formed only to provide the pin-receivinggroove above described, though desirably the lower end 60 thereof isflared to facilitate caster-pin entrance. To facilitate assembly, bothends of the stamping 30 may be provided with flared portions 60, asshown, thus making it a matter of indifference which end of the stampingis uppermost.

A bumper 64 of resilient rubber-like material is provided to snugly fitaround and under the leg-end. The bumper shown is a one-piece moldedelement, and comprises an upstanding flange having side portions 66adapted to extend along the leg-walls 24and an end portion 68 adapted toextend across the leg-wall 28, the flange 66-68 being integral with ahorizontal web 70. As shown in Fig. 7, such bumper flange 66-68desirably is formed to have a greater inward inclination than that whichthe leg-walls 24-28 may have, so that when the bumper 64 is in place theupper edges of the flange 66-68 will be resiliently stretched to assuresnug contact of at least the upper edges thereof with the leg walls. Theoffset of the flange-portion 68 is to accommodate a trim-strip 72, yetto be described.

The web 70 of the bumper 64, when the bumper is installed, underlies theinturned lips 26 of the leg walls. Centrally of such bumper-web 70, itis provided with an opening 74 adapted to receive the caster pin 36 ofthe caster 40. Desirably, the inner wall 75 of such opening is solocated with respect to the flange-portion 68 that it will be necessaryto stretch the web between the opening 74 and the flange-portion 68 tobring the opening 74 sufiiciently into alignment with the socket 30-32to permit insertion of the caster pin 36. This arrangement insures thatwith the caster in place the flange-portion 68 will be held tightlyagainst the end of the leg.

The caster which I prefer to employ in practicing my invention is one ofthe anti-friction type embodying a stationary dish-like race 76 and aseries of balls 77 interposed between such race and the upper wall ofthe conventional caster-yoke 78. The lips 26 on the chair-legs extendinwardly far enough to overlap the race '76, which constitutes ashoulder through which and the bumperweb 70 the weight of the chair andits occupant is trans mitted to the caster. The bumper-web, thus beingclampedd firmly between the race 76 and the lips 26, the bumper is heldsecurely in position. The antifriction bearing provided by the balls 77reduces any tendency of the bumper to be displaced when the casterrotates about the axis of its pin 36. The socket 30-32 is located highenough in the leg to avoid intereference with the clamping of the bumperweb between the race 76 and lips 26.

As shown, a longitudinal trim-strip 72 overlies the top leg wall 28.Such trim-strip desirably is connected inwardly of the leg-end as at 80(see Fig. 2) and in its outward run therefrom covers the rivet 56 andthe outer wall of the tongue-hook 46, to end underneath the chairleg-structure. The inner wall of the tongue-hook 46 convenientlyprovides ample means for connection of the trim-strip to the leg-bottom,as the trim-strip 72 may be secured thereto merely by hooking its endupwardly against such inner wall of the tongue-hook 46, as shown in Fig.3. Position of the trim-strip hook so formed is aided somewhat by thebumper, which conceals the lower end of the trim-strip as well as theentire caster-socket.

Desirably, such trim-strip 72 is not flat in cross-section, but is ofshallow inverted U-shape. adds to appearance and strength andaccommodates the upstanding head of the rivet 56. To support the raisedintermediate portion of the trim-strip so formed, the legwall 28 isdesirably provided with one or more upwardly struck bosses 88. Suchbosses protect against unsightly deformation of the trim-strip which maybe occasioned by a kick or other force applied to the trim-strip,especially if such force be applied in the region of the protruding headof rivet 56.

Although I have shown and described a specific embodiment of myinvention, I intend to cover all changes and modifications of theexample herein chosen for purposes of disclosure, which do notconstitute departures from the spirit and scope of the invention as setforth in the appended claims.

I claim as my invention:

1. In an article of furniture, a base having an outwardly Suchconstruction 2. The invention of claim 1 with the addition that said endwall and the groove receiving it are curved in horizontal plan to locatethe lower end of the socket transversely of the leg.

3. In an article of furniture, a base having an outwardly projecting,generally horizontal leg of sheet metal formed into an inverted U-shapein cross-section, a casterpin socket located within and secured to saidleg near its outer end, said socket comprising a pair of opposedsheet-metal stampings formed to provide opposed grooves cooperating todefine a passage adapted to receive a casterpin, and means for securingsaid stampings together, one of said stampings having at its lower endan outwardly projecting tongue having an upwardly opening hook-like end,said leg having an end wall the lower edge of which is received in saidhook-like end, one of said stampings having at its upper end an earwhich extends along and is secured to the upper wall of said leg.

4. In an article of furniture, a base having an outwardly projecting,generally horizontal leg of sheet metal formed into an inverted U-shape,a caster-pin socket located within and secured to said leg near itsouter end, said socket having a vertical passage adapted to receive acaster-pin and being provided at its lower end with an outwardlyprojecting tongue formed at its outer end with an upwardly openinggroove, said leg having an end wall the lower edge of which is receivedin said groove to locate the lower end of the socket in the leg, saidsocket having at its upper end an ear which extends along and is securedto the upper wall of said leg to locate the upper end of the socket inthe leg, the lower edges of the side walls of the leg being bentinwardly adjacent said socket to provide coplanar lips the inner edgesof which are spaced apart to permit passage of the casterpin into thesocket, and an annular thrust-transmitting bearing member surroundingthe caster-pin and underlying said lips to transmit vertical forces fromthe caster to the leg through said lips and independently of saidsocket.

projecting, generally horizontal leg of sheet metal formed into aninverted U-shape in cross-section, a caster-pin socket located withinand secured to said leg near its outer end, said socket comprising apair of opposed sheetmetal stampings formed to provide opposed groovescooperating to define a passage adapted to receive a casterpin, one ofsaid stampings having at its lower end an outwardly projecting tonguehaving a first portion which slopes upwardly, a second portion whichextends downwardly, and a third portion which extends upwardly inopposed spaced relation to said second portion to define an upwardlyopening groove the bottom of which lies approximately at the same levelas the lower end of said passage, said leg having an integral end wallthe lower edge of which is received in said last mentioned groove tolocate the lower end of the socket longitudinally of the leg.

5. The invention of claim 4 with the addition of a bumper formed ofresilient material, said bumper having a horizontal web interposedbetween said bearing member and said lips and a marginal flangeextending upwardly for a distance along the side and end walls of theleg.

References Cited in the file of this patent UNITED STATES PATENTS

